Atom-efficient electrophilic aromatic nitration by dinitrogen pentoxide catalysed by zirconium(IV) 2,4-pentanedionate.
Org Biomol Chem
; 2(1): 90-2, 2004 Jan 07.
Article
en En
| MEDLINE
| ID: mdl-14737664
An atom-efficient, non-acidic, catalytic process is described for the nitration of electron deficient arenes such as o-nitrotoluene using a dinitrogen pentoxide-zirconium(iv) 2,4-pentanedionate system in dichloromethane solvent. Kinetic studies showed the nitration process to be first-order with respect to the aromatic substrate and higher than first-order with respect to the catalyst. Addition of the catalyst at ca. 0.1-1 mol% compared with both N(2)O(5) and the organic substrate results in an increase in the first-order rate constant for nitration by a factor of approximately 5000 with a turnover number of at least 500. The orientation of the nitration products (2,4-/2,6-dinitrotoluenes) is consistent with attack of nitronium ion. The apparently high order of reaction with respect to the catalyst suggests a possible heterogeneous process.
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01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Org Biomol Chem
Asunto de la revista:
BIOQUIMICA
/
QUIMICA
Año:
2004
Tipo del documento:
Article
Pais de publicación:
Reino Unido